McHenry County, IL Swimming Pools & Spas: Fencing & Safety Requirements (2026)

Section 8.04.100 of the McHenry County Public Health Ordinance bars putting any outdoor residential swimming pool, spa or hot tub into use until it has a compliant barrier. Under § 8.04.100(B)(3), the barrier's top must sit at least 48 inches above grade, measured on the side facing away from the pool, with no more than a 4-inch gap between grade and the barrier's bottom; an aboveground pool's own structure can serve as the barrier under the same clearance rule. Openings can't pass a 4-inch sphere, chain-link mesh is capped at 1 1/4 inches square (or 1 3/4 inches with slats), and horizontal/vertical members under 45 inches apart can have no more than 1 3/4 inches of spacing between them under §§ 8.04.100(B)(5)-(9).

Section 8.04.100(B)(11) sets a separate, stricter standard for gates: every access gate must meet the same height and opening limits as the rest of the barrier and take a locking device. A pedestrian gate must swing outward, away from the pool, and be self-closing with a self-latching device; any other gate needs a self-latching device even if it doesn't swing. If the latch's release mechanism sits lower than 54 inches off the ground, it must be mounted on the pool side of the gate, at least 3 inches below the gate's top, with no opening bigger than 1/2 inch within 18 inches of the release. Pools built before January 1, 1992 may qualify for a variance of up to 15% from the measurement specs, or a full exemption if more than 500 feet from a neighboring residence, reviewed by the Department of Planning & Development, which can approve a five-year variance within 10 days of a completed petition.